Alertness/drowsiness and cognitive capacity index
First Claim
Patent Images
1. A method comprising:
- transforming a EEG signal to the frequency domain with a Discrete Fourier Transform using a processor,obtaining an amplitude of each frequency component using the processor,summing all of the amplitudes of frequencies in the range of 201-500 Hz to obtain a high frequency amplitude using the processor,summing all of the amplitudes of frequencies in the range of 1 to at least 15 Hz to obtain a low frequency amplitude using the processor, andcalculating an Index based on a ratio of the high frequency amplitude to the low frequency amplitude using the processor.
1 Assignment
0 Petitions
Accused Products
Abstract
The invention includes a method and system for providing an Index representing the alertness state of an individual based at least in part on EEG signals obtained from the individual. In at least one embodiment, the EEG signals are divided into frequency bands and a total amplitude of the power is determined. Based on the proportion of the high frequency band compared to the proportion of the low frequency band, an Index is determined that is indicative of an individual'"'"'s ability to perform a cognitive task.
-
Citations
28 Claims
-
1. A method comprising:
-
transforming a EEG signal to the frequency domain with a Discrete Fourier Transform using a processor, obtaining an amplitude of each frequency component using the processor, summing all of the amplitudes of frequencies in the range of 201-500 Hz to obtain a high frequency amplitude using the processor, summing all of the amplitudes of frequencies in the range of 1 to at least 15 Hz to obtain a low frequency amplitude using the processor, and calculating an Index based on a ratio of the high frequency amplitude to the low frequency amplitude using the processor. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18)
-
-
19. A method for determining an index representative of the level of alertness/drowsiness of an individual comprising:
-
receiving an EEG signal from at least one electrode, transforming the EEG signal into the frequency domain using a processor, summing all of the amplitudes for each frequency band using the processor, determining a total amplitude for all frequency bands using the processor, determining the ratio of each frequency band to the total amplitude for at least the lowest and highest frequency band using the processor, determining the index of the highest frequency band ratio to the lowest frequency band ratio using the processor, and providing the index using the processor; and wherein the highest frequency band begins above 60 Hz and has an end point that is less than or equal to 500 Hz. - View Dependent Claims (20, 21, 22, 23, 24, 25, 26)
-
-
27. A system comprising:
-
means for transforming an EEG signal to the frequency domain with a Discrete Fourier Transform, means for obtaining the amplitude of each frequency component, means for summing all of the amplitudes of each frequency component to obtain a total amplitude, means for summing all of the amplitudes of frequencies in the range of 201-500 Hz to obtain a high frequency amplitude, means for summing all of the amplitudes of frequencies in the range of 1 to at least 15 Hz to obtain a low frequency amplitude, and means for calculating an Index based on the total amplitude, the high frequency amplitude, and the low frequency amplitude.
-
-
28. A system for providing an index for an individual using at least one EEG signal, said system comprising:
-
a Discrete Fourier transformer; a low frequency path connected to an output of said Discrete Fourier transformer, said low frequency path includes a low bandpass filter covering the low frequency band, and a low frequency summation device connected to said low bandpass filter; a high frequency path connected to an output of said Discrete Fourier transformer, said high frequency path includes a high bandpass filter covering the high frequency band, and a high frequency summation device connected to said high bandpass filter; and a divider connect to said low frequency summation device and said high frequency summation device, said divider outputs a ratio of the output of said high frequency summation device to the output of said low frequency summation device.
-
Specification